[Objective] To improve the efficiency and accuracy of soil and water loss sampling survey, in order to reduce the difficulty and cost.[Methods] First, photos with a certain amount of overlap covering the survey area were taken by the unmanned aerial vehicle (UAV). The ortho images and DEMs were then obtained by using the tilt photogrammetry technology, geometric processing, multi view matching, triangular mesh (TIN) construction and automatic processing. Instead of the traditional way of working and technical process, the boundary and attribute information of different plots in the investigation area was obtained by artificial interpretation.[Results] The application of micro roter UAV improved the accuracy of the land boundary effectively, reduced the difficulty and cost of the field survey, and greatly saved the time of investigation.[Conclusion] The application of micro rotor UAV technique has improved the reliability of soil and water loss assessment results, and is of great importance for promoting the application of sample survey methods in the evaluation of soil erosion in all levels of government, as well as the development of soil erosion quantification technology.